To sign "hives" what you do is you show the sign "red" and then you use a "classifier F" (CL:F) to show "round blotches" on your arm -- or wherever the blotches are in real life. For example, if the blotches are on your neck or face then do the sign on your neck or face accordingly. Also, if you are talking about "hives" a lot in the same conversation you can (should) drop the sign for RED after the first time thus reducing the number of movements in the sign and making it more efficient. This sign is also sometimes done with "claw" hands if the hives are very small and numerous (more like chicken pox).
HIVES:
Notes: